26 research outputs found

    A Big Bang–Big Crunch Type-2 Fuzzy Logic System for Machine-Vision-Based Event Detection and Summarization in Real-World Ambient-Assisted Living

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    The area of ambient-assisted living (AAL) focuses on developing new technologies, which can improve the quality of life and care provided to elderly and disabled people. In this paper, we propose a novel system based on 3-D RGB-D vision sensors and interval type-2 fuzzy-logic-based systems (IT2FLSs) employing the big bang-big crunch algorithm for the real-time automatic detection and summarization of important events and human behaviors from the large-scale data. We will present several real-world experiments, which were conducted for AAL-related behaviors with various users. It will be shown that the proposed BB-BC IT2FLSs outperform the type-1 fuzzy logic system counterparts as well as other conventional nonfuzzy methods, and the performance improves when the number of subjects increases

    Longitudinal response of an existing cast iron tunnel subjected to parallel piggy-back tunnelling

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    Tunnelling close beneath an existing tunnel is a common occurrence in an urban environment. Alignment of these tunnels range from a perpendicular undercrossing to perfectly parallel. The latter is much less common, thus much less understood. Conventional assessment methods impose greenfield soil displacements directly on the existing tunnel as a worst case scenario, often leading to high estimates of longitudinal radius of curvature which are beyond the allowable design limit. Subsequently, costly and time consuming mitigation measures would have to be designed and mobilised. The scarcity of high quality case studies of parallel piggy-back tunnelling impedes the continuous effort to understand and improve the efficiency of such impact assessments; this paper presents a detailed case study which focuses on the longitudinal response of an existing 3m diameter, a century old cast iron Royal Mail tunnel that is affected by the construction of an approximately 12m diameter platform tunnel in a parallel piggy-back scenario just 2m directly beneath. Various state-of-the-art instrumentation systems including distributed fibre optic strain sensing, photogrammetry and vibrating wire instrumented bolts and electronic displacement transducers were deployed over a 40m section of the existing Royal Mail tunnel to monitor its response. This enabled the full response of the existing tunnel to be captured in a high level of detail in terms of strain and displacements as the tunnelling face progressed towards and beyond the zone of monitoring for both the pilot and tunnel enlargement phases

    Tunnelling close beneath an existing tunnel in clay – perpendicular undercrossing

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    A series of centrifuge model tests in clay was carried out to investigate the response of an existing tunnel at different clear distances to new tunnelling. A three-dimensional (3D) staged tunnelling model was adopted to simulate a wide range of tail void volume losses for the new tunnel construction while monitoring detailed 3D soil surface settlements and tunnelling-induced strains in the existing tunnel lining. This paper also presents a detailed case study of a similar scenario in the London Underground redevelopment of Bond Street station; various state-of-the-art instrumentation methods, including fibre optic Brillouin optical time domain reflectometry, instrumented tunnel bolts and photogrammetry, were deployed to monitor the response of the existing Royal Mail tunnel due to the new tunnelling works close beneath. The combination of field and centrifuge modelling data provides important new insights into the deformation mechanisms encountered in such complex tunnelling scenarios

    Monitoring the behaviour of an existing royal mail tunnel: London underground bond street station upgrade works

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    The response of existing tunnels to adjacent new tunnelling works is an area of special interest to both civil engineering designers and tunnelling engineers as well as asset owners. Field monitoring is critical as it provides vital data about the response of the existing tunnels that informs future design improvements. This paper focuses on the response of the existing, near century-old royal mail tunnel in the vicinity of bond street London underground station in London, UK. Cambridge's 'Centre for smart infrastructure and construction' (CSIC) deployed various state-of-the-art instrumentation systems to investigate the behaviour of the existing royal mail tunnel during the construction of a new passenger tunnel as part of London underground bond street upgrade scheme. The instrumentation includes distributed fibre optic strain sensing (DFOS), photogrammetry and strain gauge instrumented tunnel bolts. The monitoring systems combined were able to provide a very good insight into the existing Royal Mail tunnel behaviour, as the construction of the new tunnel beneath was undertaken
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